Geoscience faculty member Jon Lewis worked with lead author Yoshitaka Hashimoto in Japan and co-authors Michael Stipp and Frank Wuttke in Germany to characterize the history of tectonic loading at the oceanic trench that has the longest record of great earthquakes known to humankind. The paper, published in Progress in Earth and Planetary Science, is an outgrowth of Integrated Ocean Drilling Program (IODP) Expedition 315 that Lewis and Hashimoto participated in over 10 years ago aboard the Japanese drilling vessel Chikyu.
The new results suggest that the weakly deformed sedimentary rocks above the tectonic boundary where the Philippine Sea plate is consumed under Japan record changes in stress related to changing plate-boundary friction. Many questions remain, but the suggestion that the strata might record cyclic stresses has implications for understanding the great earthquake cycle.
If you are interested in learning more, check out the many exciting projects of the IODP. Lewis serves on the Science Evaluation Panel for the IODP.
Department of Geoscience